Meaning & use
equilateral
Last updated
Meanings
adjectivenot comparable
Having all sides of the same length, especially used for triangles.
Grammar: Not usually used with 'more' or 'most'; it describes a fixed property.
Patterns
- an equilateral triangle
- equilateral shape
An equilateral triangle has three equal sides and three equal angles of 60 degrees.
The tiles were shaped like equilateral triangles and fit together perfectly.
She drew an equilateral polygon with six sides.
nouncountable
A triangle in which all three sides are equal in length.
Grammar: Short for 'equilateral triangle'; often used with 'an'.
Patterns
- an equilateral
- construct an equilateral
The teacher asked the class to draw an equilateral with a compass.
In an equilateral, each angle measures exactly 60 degrees.
He proved that the triangle was an equilateral by showing all sides were equal.
Common combinations
- equilateral triangle
- The roof was made of equilateral triangles.
- equilateral polygon
- A regular hexagon is an equilateral polygon.
- equilateral shape
- The kite was designed as an equilateral shape for stability.
Synonyms and how they differ
- equal-sided
- A plain descriptive term; 'equilateral' is the standard mathematical word.
Opposites
Word family
- equilateral noun
- A triangle with all sides equal.
Commonly confused: equilateral or equiangular?
equilateral vs equiangular
Equiangular means all angles are equal, while equilateral means all sides are equal. In triangles, one implies the other, but in other polygons they can differ.
Practice
Which statement is true about an equilateral triangle?
Choose one answer.
An equilateral triangle is defined by having all three sides equal. A triangle with only two equal sides is isosceles, and one with no equal sides is scalene.
Make it your own
Write a sentence using “equilateral”, then check it and compare it with the examples above.